1. Field of the Invention
The present invention is directed generally to creating a snapshot of data.
2. Description of the Related Art
Conventional approaches have been used to create snapshots of file system data that represent the state of the data at the time the snapshot was taken. Consequently, snapshots are static in that they do not change as the underlying file system data changes. Their utility has been proven in areas for backup and recovery of file system data and in tracking changes to data that occur over a period of time.
Conventional approaches are able to take snapshots without having to copy all the file system data thus drastically reducing storage requirements. Unfortunately, these conventional approaches typically copy all the directory information of the file system as part of the snapshot. This directory information by itself can be very large thereby lowering system performance and increasing storage requirements. More recent approaches have been able to reduce the amount of directory information required for each snapshot, however, these approaches still focus on the file level whereas much of the time, modifications do not occur on entire files but rather on portions of the files.